An Equational Object-Oriented Data Model and its Data-Parallel Query Language

by Susumu Nishimura, Atsushi Ohori, Keishi Tajima


This paper presents an equational formulation of an object-oriented data model. In this model, a database is represented as a system of equations over a set of oid's, and a database query is a transformation of a system of equations into another system of equations. During the query processing, our model maintains an equivalence relation over oid's that relates oid's corresponding to the same “real-world entity.” By this mechanism, the model achieves a declarative set-based query language and views for objects with identity. Moreover, the query primitives are designed so that queries including object traversal can be evaluated in a data-parallel fashion.

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BibTex entry


object-oriented database, query language, restructuring, declarative, view, parallel processing, entity, recursive type, graph structure, object transformation
Published in Proc. of ACM OOPSLA, pp.1-18, Oct. 1996, San Jose, CA.

Copyright © 1996 by the Association for Computing Machinery, Inc. Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page.
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